<style>
    .progress-container {
      background-color: #f0f0f0;
      border-radius: 10px;
    }
  
    .progress-bar {
      width: 0;
      height: 20px;
      background-color: #4caf50;
      border-radius: 10px;
      transition: width 0.5s ease;
      text-align: center;
    }
</style>

<dom>
    <div class="progress-container">
      <div $="bar" class="progress-bar"></div>
    </div>
</dom>